21013230123 has 24 divisors (see below), whose sum is σ = 32693806080. Its totient is φ = 12967487280.

The previous prime is 21013230071. The next prime is 21013230131. The reversal of 21013230123 is 32103231012.

21013230123 is a `hidden beast` number, since 210 + 132 + 301 + 23 = 666.

It is not a de Polignac number, because 21013230123 - 2¹⁶ = 21013164587 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21013230096 and 21013230105.

It is not an unprimeable number, because it can be changed into a prime (21013230023) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1630893 + ... + 1643726.

It is an arithmetic number, because the mean of its divisors is an integer number (1362241920).

Almost surely, 2^21013230123 is an apocalyptic number.

21013230123 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

21013230123 is a deficient number, since it is larger than the sum of its proper divisors (11680575957).

21013230123 is a wasteful number, since it uses less digits than its factorization.

21013230123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3274679 (or 3274676 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

Adding to 21013230123 its reverse (32103231012), we get a palindrome (53116461135).

The spelling of 21013230123 in words is "twenty-one billion, thirteen million, two hundred thirty thousand, one hundred twenty-three".